SCIENTIFIC
South Africa’s massive sardine run leads fish into an ecological trap
Winter in KwaZulu-Natal is synonymous with the sardine run, when uncountable numbers of sardines travel from the Cape to KZN, bringing heightened excitement all along the east coast. In addition to the enthusiasts who flock to net the sardines, gamefish anglers target the predators that closely follow the little fish. Until recently it has been a great mystery as to why this migration happens. Scientists examined the DNA sequences of 284 sardines captured along the South African coast to try to 12 • SKI-BOAT July/August 2022
answer this question. In anticipation of this year’s sardine run, we republish this article which originally appeared on The Conversation, in which scientists reveal why the little silver fish migrate, even if it inevitably ends badly for them. By Peter Teske, University of Johannesburg; Carl van der Lingen, University of Cape Town; Christopher David McQuaid, Rhodes University, and Luciano Beheregaray, Flinders University.
NE of the world’s most spectacular marine migrations is the KwaZulu-Natal sardine run. The so-called “greatest shoal on Earth” takes place during the southern hemisphere’s winter. It involves the movement of tens to hundreds of millions of sardines from the warm, temperate waters of South Africa’s south coast to the subtropical waters of the east coast, over a thousand kilometres away. This annual mass migration, first reported in 1853, is triggered by cold
O
